This invention relates to a structure for enhancing aquatic habitats for fish and mobile shellfish, and more specifically to an artificial reef which may be used to protect existing natural reefs or to substitute for damaged or destroyed natural reefs.
Currently more than fifty percent (50%) of the population of the United States resides in the coastal areas of the country. This increased population and concomitant increased use of the coastal environment has resulted in general degradation of the coastal marine environment and increased stress on the habitats of coastal aquatic life.
The coastal population in attempting to restrict the natural changes in the coastline has constructed barriers, such as seawalls, to limit the eroding action of waves on shoreline property. The installation of seawalls has caused an increase in the vertical force of wave action resulting from the abrupt limitation of the horizontal wave movement by seawalls as well as other man-made coastal barriers. This redirection of wave forces has caused the destruction of natural reefs and other aquatic habitats from the deposit of sand and other materials carried back out to sea by receding water currents. In addition, the increased recreational and fishing activity resulting from the coastal population increase has both heightened the demand for fish and shellfish while reducing the suitable habitat to sustain epibenthic colonization.
One means of reducing damage to natural reefs has been to erect structures between the reef and the shoreline so as to reduce the wave force effect upon natural reefs. These artificial reefs have generally consisted of large steel, stone or concrete barriers which serve to intercept the wave forces and protect natural reefs. Generally such artificial reefs have consisted of substantially solid barriers with openings so that seawater can move through the artificial reef with some freedom and yet be slowed so as to reduce the impact upon the natural reef areas. While presently available artificial reefs do provide a means to redirect wave forces and thus lessen the impact on natural reefs, they generally lack appropriate design features which are attractive to sea life for habitation and reproduction.
The lack of features in artificial reefs which are amenable to the habitat of coastal aquatic life narrows their utility to that of simple maintenance of existing natural reefs and generally does not contribute to an increase in habitat area or improvement of the coastal marine environment. More importantly, in coastal areas where natural reefs have been virtually destroyed presently available mechanical reefs fail to provide the complex shape desired by marine life for inhabitation. In addition if the mechanical reefs are constructed of wood or metal the deterioration of these substances in salt water can prove undesirable for long term inhabitation by marine life.
Therefore, an important object of the present invention is to provide a mechanical reef structure that provides a complex shape which encourages both calm and turbulent water flow while avoiding areas of water stagnation and through its complex shape provides a habitat suitable to aquatic life.
Another objective is to provide an artificial reef structure which provides a large amount of surface area suitable for colonization by marine life.
It is also an objective of the present invention to provide a cost effective artificial reef in terms of maximum exposed surface area per dollar invested.
Another objective is to provide design flexibility of the reef through use of modular design components which may be constructed either on the job site or at some distance and then rapidly deployed to the desired reef location.
It is also an objective of the present invention to provide a cost effective aquatic reef which is constructed of inert and non-corroding components that will neither harm the marine environment nor rapidly be destroyed by the corrosive effect of salt water.
Yet another objective of the present invention is to provide an artificial reef which may serve as either an optional aquatic habitat for marine life or which can provide protection for already existing natural reefs while increasing the suitable aquatic habitat in the vicinity of the natural reef.
A further objective of the present invention is to provide an artificial reef which may easily and conveniently be transported to and affixed in the selected site.